Changes in the Prevalence and Risk Factors of Erectile Dysfunction during a Decade: The Korean Internet Sexuality Survey (KISS), a 10-Year-Interval Web-Based Survey

Purpose

Although the prevalence of erectile dysfunction (ED) can be affected by social changes, this association has not been well evaluated. We aimed to evaluate the prevalence and risk factors of ED through a 10-year-interval web-based survey using the previous database of same group of panels, with same methodology.

Materials and Methods

We sent e-mails and surveyed the panels registered in the Internet survey agency.

Results

In total, 900 participants were recruited in 2016. The age-adjusted overall prevalences of self-reported ED (self-ED) and International Index of Erectile Function-5-assessed ED (IIEF-5-ED; score ≤21) in the 2016 study were 3.2% and 44.8%, respectively, which were lower than the prevalences of 8.1% (p=0.036) and 51.4% (p=0.323), respectively, in the 2006 study. The risk factors of IIEF-5-ED in their 20s and 30s in 2016 were psycho-social factors such as depression, low frequency of conversation about sex with sexual partner. The risk factors of IIEF-5-ED in their 40s to 60s in 2016 were organic factors, such as hypertension, diabetes mellitus, smoking, alcohol use, and self-reported premature ejaculation.

Conclusions

Although the age-adjusted overall prevalence of self-ED has decreased during a decade, there was no difference in the age-adjusted overall prevalence of IIEF-5-ED. Psycho-social support may be important for young men with ED and overall healthcare can be helpful for elderly men with ED.

Does epithelioid angiomyolipoma have poorer prognosis, compared with classic angiomyolipoma?

Purpose

Classic angiomyolipoma (AML) is common benign kidney tumor. However, some studies have claimed that epithelioid angiomyolipoma (EAML) has malignant potential. We compared the patient characteristics and prognosis of EAML and classic AML to demonstrate predicting factors and poorer prognosis of EAML.

Materials and Methods

The medical records of 231 patients who were diagnosed with EAML (n=27, 11.7%) or classic AML (n=204, 88.3%), were reviewed. All patients underwent computed tomography (CT) scans before operation or needle biopsy. We assessed the age, sex, tumor size, body mass index, comorbidities, and Hounsfield unit (HU) according to each CT phase. We defined the unfavorable group as patients with recurrence, metastasis and death due to tumor progression. Logistic regression analysis was used to predict EAML.

Results

EAML patients were younger (41.2 years vs. 49.1 years, p=0.001), predominantly male (55.6% vs. 28.4%, p=0.005), and had a larger tumor (7.5 cm vs. 4.2 cm, p<0.001). The median pre-contrast HU was not significantly different between EAML and classic AML (29.9±23.7 vs. 14.7±41.0, p=0.071). In multivariable analysis, younger age (odds ratio [OR], 0.96; p=0.032), male sex (OR, 3.33; p=0.013), and tumor larger than 4 cm (OR, 3.8; p=0.009) were significant predictive factors. Five patients (18.5%) had unfavorable outcomes, two patients had lymph node metastasis, and three patients had lung metastasis.

Conclusions

Patient and tumor characteristics can be helpful in determining the type of AML preoperatively. Younger age, male sex, and larger tumor mass may increase the possibility of diagnosing EAML. EAML has malignant potential and requires careful follow-up.

Growth kinetics of Kr nano structures encapsulated by graphene

Graphene can acquire salient properties by the intercalated nano structures, and to functionalize the graphene as designed, understanding the growth kinetics of the nano structures is a prerequisite. In that regards, Kr atoms are selectively intercalated just below the surface graphene of C(0001) by the incidence of low energy Kr ions. The growth kinetics of the encapsulated Kr nano structures is investigated by both scanning tunneling microscopy and molecular dynamics simulations. The intercalation proceeds via defect sites, such as surface vacancies. At room temperature, the thermal diffusion of intercalated Kr is almost frustrated by the strain field of the encapsulating graphene layers, and the growth of Kr nano structures proceeds via the transient mobility of both the intercalating Kr atoms and previously intercalated Kr atoms that are mobilized by collision with the incident Kr ions. At the elevated temperatures where thermal diffusion becomes effective, some Kr nano structures disappear, releasing pressurized Kr atoms, while others coalesce to form blisters via the delamination of the adjacent graphene. Some of the larger blisters explode to leave craters of varying depths at the surface. In contrast to growth on the substrate, the growth of each encapsulated nano structure depends significantly on extrinsic variables, such as surface vacancies and local topography around the nano structure, that affect the Kr diffusion and limit the maximal Kr pressure.

Effects of Progressive Resistance Training on Post-Surgery Incontinence in Men with Prostate Cancer

We evaluated the efficacy of progressive resistance training of the pelvic floor muscle for post-prostatectomy incontinence. In this prospective study, 59 patients who underwent radical prostatectomy were evaluated preoperatively. Continence was sequentially assessed within 2 weeks postoperatively, and an exercise regimen was initiated at 6- and 12-weeks. The primary outcome was continent status and the secondary outcome was changes in muscle strength and endurance after the exercise intervention. Continence was defined as no urine loss in a 1h pad test. A total of 59 patients participated in this study. Six patients dropped out of the study because of non-compliance and orthopedic problems. Of the remaining 53 patients, 31 (58.5%) achieved pad-free continence at 12 weeks postoperatively. The patients were divided into two groups based on their continence status, and no statistically significant difference was observed in age, body mass index, prostate volume, prostate-specific antigen, pathological Gleason score sum, and pathological T stage. Meanwhile, preoperative maximal urethral closure pressure and change in hip extensor muscle strength and endurance during the 12-week exercise program were significantly higher in the continent group. In multivariate analysis, change in hip extensor muscle strength was the only significant parameter predicting achievement of continence status (Odds ratio, 1.039; p = 0.045). The changes in hip extensor muscle strength in the current exercise program was an independent predictor of continence status after radical prostatectomy. A large-scale prospective study on the relationship between extensor muscle strength and urinary incontinence should be explored in future.

Single dose partial breast irradiation using an MRI linear accelerator in the supine and prone treatment position

Background

In selected patients with early-stage and low-risk breast cancer, an MRI-linac based treatment might enable a radiosurgical, non-invasive alternative for current standard breast conserving therapy.

Aim

To investigate whether single dose accelerated partial breast (APBI) to the intact tumor in both the prone and supine radiotherapy positions on the MRI-linac is dosimetrically feasible with respect to predefined coverage and organs at risk (OAR) constraints.

Material & methods

For 20 patients with cTis or low-risk cT1N0M0 non-lobular breast carcinoma, previously treated with single dose preoperative APBI in the supine (n = 10) or prone (n = 10) position, additional intensity modulated radiotherapy plans with 7 coplanar beams in the presence of a 1.5T magnetic field were generated. A 20 Gy and 15 Gy dose was prescribed to the gross tumor and clinical target volume, respectively. The percentage of plans achieving predefined organ at risk (OAR) constraints, currently used in clinical practice, was assessed. Dosimetry differences between the prone versus supine approach and the MRI-linac versus clinically delivered plans were evaluated.

Results

All MRI-linac plans met the coverage and predefined OAR constraints. The prone approach appeared to be more favorable with respect to the chest wall, and ipsilateral lung dose compared to the supine position. No dosimetric differences were observed for the ipsilateral breast. No treatment position was clearly more beneficial for the skin or heart, since dosimetry varied among parameters. Overall, the MRI-linac and clinical plans were comparable, with minor absolute dosimetric differences.

Conclusion

MRI-linac based single dose APBI to the intact tumor is a promising and a dosimetrically feasible strategy in patients with low-risk breast cancer. Preliminary OAR dosimetry favored the prone radiotherapy position.

Usefulness of the frequency-volume chart over the International Prostate Symptom Score in patients with benign prostatic hyperplasia in view of global polyuria

Purpose

We aimed to determine the usefulness of the frequency-volume chart over the International Prostate Symptom Score in patients with benign prostatic hyperplasia. Furthermore, we investigated the clinical characteristics suggesting that patients could benefit from frequency-volume chart assessment in addition to International Prostate Symptom Score assessment.

Methods

A total of 193 patients with benign prostatic hyperplasia were analyzed. The relationship between the information obtained from the frequency-volume chart and the International Prostate Symptom Score was assessed. Because the urine output per kilogram per hour was not associated with any question in the International Prostate Symptom Score questionnaire, patients were divided into 2 groups according to the presence of global polyuria, defined as urine output >40 mL·kg^-1·h^-1. Multivariable analysis was performed to determine the predictors of global polyuria, and the results were externally validated using 397 patients with benign prostatic hyperplasia.

Results

Although the other information obtained from the frequency-volume chart correlated with the International Prostate Symptom Score, the urine output was not associated with the International Prostate Symptom Score. Based on these results, patients were dichotomized into the global polyuria group (n = 19, 9.8%) and the non-global polyuria group. Although the patient characteristics did not differ between the 2 groups, the number of voids was higher in patients with global polyuria. Multivariable analysis showed that diabetes mellitus (odds ratio: 3.497, p = 0.039) and increased number of voids (odds ratio: 1.320, p < 0.001) were significant predictors of global polyuria. On external validation, the area under curve for the model was 0.723.

Conclusions

Global polyuria cannot be suspected using the International Prostate Symptom Score, although it worsens the lower urinary tract symptoms of patients with benign prostatic hyperplasia. Assessment with the frequency-volume chart needs to be considered in diabetic patients with increased number of voids.

Declining incidence of benign lesions among small renal masses treated with surgery: Effect of diagnostic tests for characterization

PURPOSE

We evaluated the changes in the incidence of benign lesions in surgically removed small renal masses (SRMs) and the effect of diagnostic tests for characterizing SRMs.

METHODS

We included 2,707 patients receiving surgery for SRMs (<4cm). Trends in the incidence of benign histology were evaluated according to the surgery year (period 1: 2001-2005, 2: 2006-2010, and 3: 2011-2015). Multivariable logistic regression analysis was performed to identify factors associated with benign lesions. Additionally, the number of surgeries prevented due to benign histological findings on renal mass biopsies (RMB) done on 206 patients with SRM during study period was evaluated.

RESULTS

Benign histology was identified in 192 (7.1%) patients. Incidence of benign histology was 9.7%, 7.0%, and 6.3% for period 1, 2 and 3, respectively. The uses of multiphase computed tomography and magnetic resonance imaging were more common in periods 2 and 3 than in period 1 (P<0.001). The use of RMB in period 3 was higher than in periods 1 and 2 (0.8 vs. 0.9 vs. 9.0%, P<0.001). In multivariable analysis, older age, male sex, larger tumor size, and recent surgery year (period 3 vs. 1, odds ratio = 0.62, P = 0.028) were independently associated with decreased odds of benign lesions. The number of prevented surgeries by performing RMB was 0, 10, and 39 in periods 1, 2, and 3, respectively.

CONCLUSIONS

Incidence of benign histology after surgery for SRMs declined during recent years, which might be associated with the recent increased use of RMB.

Predictors for the detection of prostate cancer and clinically significant prostate cancer using TRUS-guided biopsy in patients with negative initial biopsy results

PURPOSE

We aimed to determine the predictors for the detection of prostate cancer and clinically significant prostate cancer in the setting of repeat prostate biopsy using trans-rectal ultrasonography-guided biopsy.

METHODS

A total of 636 patients who underwent repeat prostate biopsy were included. The patients were divided into two groups according to the repeat biopsy results (with vs. without prostate cancer). A multivariable analysis was performed to assess the predictors for the detection of prostate cancer and clinically significant prostate cancer.

RESULTS

Prostate cancer was detected in 98 patients (15.4%). Although there was no difference in the prostate-specific antigen velocity, the prostate-specific antigen density was higher in the patients with prostate cancer at the initial (0.14 vs. 0.17 ng/mL/cc, p = 0.049) and repeat biopsies (0.17 vs. 0.26 ng/mL/cc, p < 0.001). The proportions of the patients who met the active surveillance criteria were as follows: 22.4% (Johns Hopkins), 30.6% (University of Toronto), 32.7% (University of California at San Francisco), 30.6% (Prostate Cancer Research International Active Surveillance), 27.6% (Memorial Sloan Kettering Cancer Center), and 13.3% (University of Miami). In the multivariable analysis, age, hypoechoic lesion on trans-rectal ultrasonography, and prostate-specific antigen density at the repeat biopsy were the significant predictors for prostate cancer and clinically significant prostate cancer.

CONCLUSIONS

Trans-rectal ultrasonography before repeat prostate biopsy and the prostate-specific antigen density are useful for selecting patients with a high probability for prostate cancer if repeat trans-rectal ultrasonography-guided biopsy is considered. In addition, these are also helpful for detecting clinically significant prostate cancer.

The Clinical Efficacy of Dual-Lumen Catheter Technique in Retrograde Intrarenal Surgery for the Management of Nephrolithiasis: A Propensity Score Analysis

OBJECTIVE

To assess the clinical efficacy of dual-lumen catheter technique in retrograde intrarenal surgery (RIRS) in terms of stone-free rate.

METHODS

The data of 172 patients who underwent RIRS for renal stones between 2010 and 2017 were retrospectively reviewed. Patients were classified into two groups depending on whether the dual-lumen catheter technique was used (group 1, n = 25) or not (group 2, n = 147) during RIRS. In turn, all patients of group 1 were compared with those of group 2 using propensity score analysis methods. Clinical variables, including post-RIRS residual fragments (RFs) (≥2 mm) and dusts (sandy stones) (≤1 mm), were compared between both groups. Logistic regression analyses were conducted to identify the predictors of postoperative RFs and dusts.

RESULTS

According to propensity score analysis, no other clinical variables were significantly different between the two groups, except the dust-free rate was significantly higher in group 1 than in group 2 (92% vs 40%, p < 0.001). In multivariate analysis, the performance of dual-lumen catheter technique was an independent predictor of the absence of dusts after RIRS (odds ratio [OR], 0.040; 95% confidence interval [CI], 0.070-0.220). In addition, on performing multivariate analyses in another matched population, it was found that although the technique adversely affected the removal of RFs (OR, 4.711; 95% CI, 1.203-18.447), it showed an excellent effect on the evacuation of dusts (OR, 0.049; 95% CI, 0.007-0.347).

CONCLUSION

Our analyses suggest that the use of dual-lumen catheter during RIRS can facilitate the evacuation of sandy stones. However, further prospective randomized trials are required to verify the usefulness of this technique in real clinical practice.

Combination of Androgen Deprivation Therapy and Salvage Radiotherapy versus Salvage Radiotherapy Alone for Recurrent Prostate Cancer after Radical Prostatectomy

INTRODUCTION

To assess the value of androgen deprivation therapy (ADT) on salvage radiotherapy (RT) in post-prostatectomy recurrent prostate cancer patients, we compared the oncologic outcomes between patients receiving RT + ADT and those receiving RT alone.

MATERIALS AND METHODS

We reviewed the records of patients diagnosed with prostate cancer between 1995 and 2011, including 93 patients who underwent salvage RT and 69 patients who underwent salvage RT + ADT. The ADT-free duration after withdrawal was calculated to verify testosterone recovery.

RESULTS

Presalvage prostate serum antigen (PSA) was the only significantly different characteristic between the 2 groups (p < 0.001). The ADT-free duration was greater than 6 months in >80% of patients. Presalvage PSA ≥0.6 ng/mL, pathologic stage ≥T3b, and RT + ADT were significantly associated with biochemical progression after salvage treatment. RT + ADT reduced biochemical progression in patients with seminal vesicle invasion or presalvage PSA ≥0.6 ng/mL (p = 0.001) compared to RT alone; biochemical progression-free probability was unchanged in seminal vesicle noninvasive prostate cancer patients with presalvage PSA <0.6 ng/mL (p = 0.541).

CONCLUSIONS

RT + ADT reduced the risk of biochemical progression after salvage treatment in patients with seminal vesicle invasion or presalvage PSA ≥0.6 ng/mL, but had no effect in patients with seminal vesicle noninvasive disease and presalvage PSA <0.6 ng/mL.

A novel vaporization-enucleation technique for benign prostate hyperplasia using 120-W HPS GreenLight™ laser: Seoul technique II in comparison with vaporization and previously reported modified vaporization-resection technique

PURPOSE

We developed a novel vaporization-enucleation technique (Seoul II), which consists of vaporization-enucleation of the prostate using 120-W HPS GreenLight laser, and enucleated prostate resection using bipolar devices for tissue removal. We compared the outcomes of the Seoul II with vaporization and a previously reported modified vaporization-resection technique (Seoul I).

METHODS

Among patients with benign prostate hyperplasia who underwent transurethral surgery using GreenLight laser at our institute, 347 patients with prostate volume ≥ 40 ml were included. The impact of surgical techniques on efficacy and postoperative functional outcomes was compared.

RESULTS

No difference was found in baseline characteristics, although the prostate volume was marginally greater in Seoul II (p = 0.051). Prostate volume reduction per operation time (p < 0.001) and lasing time (p = 0.016) were greater in Seoul II. At postoperative 12 months, the International Prostate Symptom Score (I-PSS) was lower (p = 0.011), and the decrement in I-PSS was greater in Seoul II (p = 0.001) than other techniques. In multivariate analysis, postoperative 12-month I-PSS for Seoul II was significantly superior to vaporization (p < 0.001), although it was similar to Seoul I. The maintenance of immediate postoperative I-PSS decrement, until postoperative 12 months was superior in Seoul II compared with vaporization (p = 0.014) and Seoul I (p = 0.048).

CONCLUSIONS

Seoul II showed improved efficacy and voiding functional maintenance over postoperative 12 months in patients with prostate volume ≥ 40 ml compared with vaporization and Seoul I. This technique could be easily accepted by clinicians who are familiar with GreenLight lasers and add flexibility to surgery without additional equipment.

A novel biopsy-related parameter derived from location and relationship of positive cores on standard 12-core trans-rectal ultrasound-guided prostate biopsy: a useful parameter for predicting tumor volume compared to number of positive cores

PURPOSE

To develop a novel biopsy-related parameter, named overlapping line, defined as the line between the adjacent positive cores on 12-core trans-rectal ultrasound-guided prostate biopsy, and evaluated the value of overlapping line for predicting tumor volume in the final pathologic examination.

METHODS

Among patients with prostate cancer who underwent radical prostatectomy at Boramae Medical Center, 470 patients who underwent standard 12-core trans-rectal ultrasound-guided prostate biopsy were selected for the analysis. The number of overlapping line was determined in each patient, and its effects on tumor volume were evaluated after adjusting for other variables.

RESULTS

Median prostate specific antigen level was 9.1 ng/mL, and the maximum % cancer in positive cores was 42.8%. Median numbers of positive cores and overlapping lines were three and two, respectively. The pathologic stage was T2 or less, T3a, and T3b or greater in 297 (63.5%), 104 (22.2%), and 67 patients (14.3%), respectively. Median tumor volume in prostatectomy specimen was 3.4 mL. In multivariable analysis, the number of overlapping lines (B 0.750, p < 0.001) was a significant predictor for tumor volume, in addition to prostate specific antigen level and maximum % cancer in positive cores. In addition, the model with overlapping line showed superior accuracy compared to the model with positive core based adjusted r ² (0.467 vs. 0.456).

CONCLUSIONS

The number of overlapping lines, a novel prostate biopsy-related variable, is thought to be a more reliable predictor for tumor volume compared to the number of positive cores and could be easily applied to routine daily practice.

Adaptive functional change of the contralateral kidney after partial nephrectomy

Partial nephrectomy aims to maintain renal function by nephron sparing; however, functional changes in the contralateral kidney remain unknown. We evaluate the functional change in the contralateral kidney using a diethylene triamine penta-acetic acid (DTPA) renal scan and determine factors predicting contralateral kidney function after partial nephrectomy. A total of 699 patients underwent partial nephrectomy, with a DTPA scan before and after surgery to assess the separate function of each kidney. Patients were divided into three groups according to initial contralateral glomerular filtration rate (GFR; group 1: <30 ml·min−1·1.73 m−2, group 2: 30–45 ml·min−1·1.73 m−2, and group 3: ≥45 ml·min−1·1.73 m−2). Multiple-regression analysis was used to identify the factors associated with increased GFR of the contralateral kidney over a 4-yr postoperative period. Patients in group 1 had a higher mean age and hypertension history, worse American Society of Anesthesiologists score, and larger tumor size than in the other two groups. The ipsilateral GFR changes at 4 yr after partial nephrectomy were −18.9, −3.6, and 3.9% in groups 1, 2, and 3, respectively, whereas the contralateral GFR changes were 10.8, 25.7, and 38.8%. Age [β: −0.105, 95% confidence interval (CI): −0.213; −0.011, P < 0.05] and preoperative contralateral GFR (β: −0.256, 95% CI: −0.332; −0.050, P < 0.01) were significant predictive factors for increased GFR of the contralateral kidney after 4 yr. The contralateral kidney compensated for the functional loss of the ipsilateral kidney. The increase of GFR in contralateral kidney is more prominent in younger patients with decreased contralateral renal function.

Downregulation of androgen receptors by NaAsO2 via inhibition of AKT-NF-κB and HSP90 in castration resistant prostate cancer

BACKGROUND

Androgen and androgen receptor (AR) play essential roles in the development and maintenance of prostate cancer. The recently identified AR splice variants (AR-Vs) have been considered as a plausible mechanism for the primary resistance against androgen deprivation therapy (ADT) in castration-resistant prostate cancer (CRPC). Sodium meta-arsenite (NaAsO₂ ; KML001; Kominox), a trivalent arsenical, is an orally bioavailable and water soluble, which is currently in phase I/II clinical trials for the treatment of prostate cancer. It has a potent anti-cancer effect on prostate cancer cells and xenografts. The aim of this study was to examine the effect of NaAsO₂ on AR signaling in LNCaP and 22Rv1 CRPC cells.

METHODS

We used hormone-sensitive LNCaP cells, hormone-insensitive 22Rv1 cells, and CRPC patient-derived primary cells. We analyzed anti-cancer effect of NaAsO₂ using real-time quantitative reverse transcription-PCR, Western blotting, immunofluorescence staining and CellTiter Glo® luminescent assay. Statistical evaluation of the results was performed by one-way ANOVA.

RESULTS

NaAsO₂ significantly reduced the translocation of AR and AR-Vs to the nucleus as well as their level in LNCaP and 22Rv1 cells. Besides, the level of the prostate-specific antigen (PSA), downstream target gene of AR, was also decreased. This compound was also an effective modulator of AKT-dependent NF-κB activation which regulates AR. NaAsO₂ significantly inhibited phosphorylation of AKT and expression and nuclear translocation of NF-κB. We then investigated the effect of NaAsO₂ on AR stabilization. NaAsO₂ promoted HSP90 acetylation by down-regulating HDAC6, which reduces the stability of AR in prostate cancer cells.

CONCLUSIONS

Here, we show that NaAsO₂ disrupts AR signaling at multiple levels by affecting AR expression, stability, and degradation in primary tumor cell cultures from prostate cancer patients as well as CRPC cell lines. These results suggest that NaAsO₂ could be a novel therapeutics for prostate cancer.